path: root/libavfilter/af_join.c (plain)
blob: bd780cc379d5ce39afef672d3e51bcd695bdc99b

1	/*
2	* This file is part of FFmpeg.
3	*
4	* FFmpeg is free software; you can redistribute it and/or
5	* modify it under the terms of the GNU Lesser General Public
6	* License as published by the Free Software Foundation; either
7	* version 2.1 of the License, or (at your option) any later version.
8	*
9	* FFmpeg is distributed in the hope that it will be useful,
10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12	* Lesser General Public License for more details.
13	*
14	* You should have received a copy of the GNU Lesser General Public
15	* License along with FFmpeg; if not, write to the Free Software
16	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17	*/
18
19	/**
20	* @file
21	* Audio join filter
22	*
23	* Join multiple audio inputs as different channels in
24	* a single output
25	*/
26
27	#include "libavutil/avassert.h"
28	#include "libavutil/channel_layout.h"
29	#include "libavutil/common.h"
30	#include "libavutil/opt.h"
31
32	#include "audio.h"
33	#include "avfilter.h"
34	#include "formats.h"
35	#include "internal.h"
36
37	typedef struct ChannelMap {
38	int input; ///< input stream index
39	int in_channel_idx; ///< index of in_channel in the input stream data
40	uint64_t in_channel; ///< layout describing the input channel
41	uint64_t out_channel; ///< layout describing the output channel
42	} ChannelMap;
43
44	typedef struct JoinContext {
45	const AVClass *class;
46
47	int inputs;
48	char *map;
49	char *channel_layout_str;
50	uint64_t channel_layout;
51
52	int nb_channels;
53	ChannelMap *channels;
54
55	/**
56	* Temporary storage for input frames, until we get one on each input.
57	*/
58	AVFrame **input_frames;
59
60	/**
61	* Temporary storage for buffer references, for assembling the output frame.
62	*/
63	AVBufferRef **buffers;
64	} JoinContext;
65
66	#define OFFSET(x) offsetof(JoinContext, x)
67	#define A AV_OPT_FLAG_AUDIO_PARAM
68	#define F AV_OPT_FLAG_FILTERING_PARAM
69	static const AVOption join_options[] = {
70	{ "inputs", "Number of input streams.", OFFSET(inputs), AV_OPT_TYPE_INT, { .i64 = 2 }, 1, INT_MAX, A|F },
71	{ "channel_layout", "Channel layout of the "
72	"output stream.", OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, {.str = "stereo"}, 0, 0, A|F },
73	{ "map", "A comma-separated list of channels maps in the format "
74	"'input_stream.input_channel-output_channel.",
75	OFFSET(map), AV_OPT_TYPE_STRING, .flags = A|F },
76	{ NULL }
77	};
78
79	AVFILTER_DEFINE_CLASS(join);
80
81	static int try_push_frame(AVFilterContext *ctx);
82
83	static int filter_frame(AVFilterLink *link, AVFrame *frame)
84	{
85	AVFilterContext *ctx = link->dst;
86	JoinContext *s = ctx->priv;
87	int i, j;
88
89	for (i = 0; i < ctx->nb_inputs; i++)
90	if (link == ctx->inputs[i])
91	break;
92	av_assert0(i < ctx->nb_inputs);
93	av_assert0(!s->input_frames[i]);
94	s->input_frames[i] = frame;
95
96	/* request the same number of samples on all inputs */
97	/* FIXME that means a frame arriving asynchronously on a different input
98	will not have the requested number of samples */
99	if (i == 0) {
100	int nb_samples = s->input_frames[0]->nb_samples;
101
102	for (j = 1; !i && j < ctx->nb_inputs; j++)
103	ctx->inputs[j]->request_samples = nb_samples;
104	}
105
106	return try_push_frame(ctx);
107	}
108
109	static int parse_maps(AVFilterContext *ctx)
110	{
111	JoinContext *s = ctx->priv;
112	char separator = '|';
113	char *cur = s->map;
114
115	#if FF_API_OLD_FILTER_OPTS
116	if (cur && strchr(cur, ',')) {
117	av_log(ctx, AV_LOG_WARNING, "This syntax is deprecated, use '|' to "
118	"separate the mappings.\n");
119	separator = ',';
120	}
121	#endif
122
123	while (cur && *cur) {
124	char *sep, *next, *p;
125	uint64_t in_channel = 0, out_channel = 0;
126	int input_idx, out_ch_idx, in_ch_idx;
127
128	next = strchr(cur, separator);
129	if (next)
130	*next++ = 0;
131
132	/* split the map into input and output parts */
133	if (!(sep = strchr(cur, '-'))) {
134	av_log(ctx, AV_LOG_ERROR, "Missing separator '-' in channel "
135	"map '%s'\n", cur);
136	return AVERROR(EINVAL);
137	}
138	*sep++ = 0;
139
140	#define PARSE_CHANNEL(str, var, inout) \
141	if (!(var = av_get_channel_layout(str))) { \
142	av_log(ctx, AV_LOG_ERROR, "Invalid " inout " channel: %s.\n", str);\
143	return AVERROR(EINVAL); \
144	} \
145	if (av_get_channel_layout_nb_channels(var) != 1) { \
146	av_log(ctx, AV_LOG_ERROR, "Channel map describes more than one " \
147	inout " channel.\n"); \
148	return AVERROR(EINVAL); \
149	}
150
151	/* parse output channel */
152	PARSE_CHANNEL(sep, out_channel, "output");
153	if (!(out_channel & s->channel_layout)) {
154	av_log(ctx, AV_LOG_ERROR, "Output channel '%s' is not present in "
155	"requested channel layout.\n", sep);
156	return AVERROR(EINVAL);
157	}
158
159	out_ch_idx = av_get_channel_layout_channel_index(s->channel_layout,
160	out_channel);
161	if (s->channels[out_ch_idx].input >= 0) {
162	av_log(ctx, AV_LOG_ERROR, "Multiple maps for output channel "
163	"'%s'.\n", sep);
164	return AVERROR(EINVAL);
165	}
166
167	/* parse input channel */
168	input_idx = strtol(cur, &cur, 0);
169	if (input_idx < 0 || input_idx >= s->inputs) {
170	av_log(ctx, AV_LOG_ERROR, "Invalid input stream index: %d.\n",
171	input_idx);
172	return AVERROR(EINVAL);
173	}
174
175	if (*cur)
176	cur++;
177
178	in_ch_idx = strtol(cur, &p, 0);
179	if (p == cur) {
180	/* channel specifier is not a number,
181	* try to parse as channel name */
182	PARSE_CHANNEL(cur, in_channel, "input");
183	}
184
185	s->channels[out_ch_idx].input = input_idx;
186	if (in_channel)
187	s->channels[out_ch_idx].in_channel = in_channel;
188	else
189	s->channels[out_ch_idx].in_channel_idx = in_ch_idx;
190
191	cur = next;
192	}
193	return 0;
194	}
195
196	static av_cold int join_init(AVFilterContext *ctx)
197	{
198	JoinContext *s = ctx->priv;
199	int ret, i;
200
201	if (!(s->channel_layout = av_get_channel_layout(s->channel_layout_str))) {
202	av_log(ctx, AV_LOG_ERROR, "Error parsing channel layout '%s'.\n",
203	s->channel_layout_str);
204	return AVERROR(EINVAL);
205	}
206
207	s->nb_channels = av_get_channel_layout_nb_channels(s->channel_layout);
208	s->channels = av_mallocz_array(s->nb_channels, sizeof(*s->channels));
209	s->buffers = av_mallocz_array(s->nb_channels, sizeof(*s->buffers));
210	s->input_frames = av_mallocz_array(s->inputs, sizeof(*s->input_frames));
211	if (!s->channels || !s->buffers|| !s->input_frames)
212	return AVERROR(ENOMEM);
213
214	for (i = 0; i < s->nb_channels; i++) {
215	s->channels[i].out_channel = av_channel_layout_extract_channel(s->channel_layout, i);
216	s->channels[i].input = -1;
217	}
218
219	if ((ret = parse_maps(ctx)) < 0)
220	return ret;
221
222	for (i = 0; i < s->inputs; i++) {
223	char name[32];
224	AVFilterPad pad = { 0 };
225
226	snprintf(name, sizeof(name), "input%d", i);
227	pad.type = AVMEDIA_TYPE_AUDIO;
228	pad.name = av_strdup(name);
229	if (!pad.name)
230	return AVERROR(ENOMEM);
231	pad.filter_frame = filter_frame;
232
233	pad.needs_fifo = 1;
234
235	ff_insert_inpad(ctx, i, &pad);
236	}
237
238	return 0;
239	}
240
241	static av_cold void join_uninit(AVFilterContext *ctx)
242	{
243	JoinContext *s = ctx->priv;
244	int i;
245
246	for (i = 0; i < ctx->nb_inputs; i++) {
247	av_freep(&ctx->input_pads[i].name);
248	av_frame_free(&s->input_frames[i]);
249	}
250
251	av_freep(&s->channels);
252	av_freep(&s->buffers);
253	av_freep(&s->input_frames);
254	}
255
256	static int join_query_formats(AVFilterContext *ctx)
257	{
258	JoinContext *s = ctx->priv;
259	AVFilterChannelLayouts *layouts = NULL;
260	int i, ret;
261
262	if ((ret = ff_add_channel_layout(&layouts, s->channel_layout)) < 0 ||
263	(ret = ff_channel_layouts_ref(layouts, &ctx->outputs[0]->in_channel_layouts)) < 0)
264	return ret;
265
266	for (i = 0; i < ctx->nb_inputs; i++) {
267	layouts = ff_all_channel_layouts();
268	if ((ret = ff_channel_layouts_ref(layouts, &ctx->inputs[i]->out_channel_layouts)) < 0)
269	return ret;
270	}
271
272	if ((ret = ff_set_common_formats(ctx, ff_planar_sample_fmts())) < 0 ||
273	(ret = ff_set_common_samplerates(ctx, ff_all_samplerates())) < 0)
274	return ret;
275
276	return 0;
277	}
278
279	static void guess_map_matching(AVFilterContext *ctx, ChannelMap *ch,
280	uint64_t *inputs)
281	{
282	int i;
283
284	for (i = 0; i < ctx->nb_inputs; i++) {
285	AVFilterLink *link = ctx->inputs[i];
286
287	if (ch->out_channel & link->channel_layout &&
288	!(ch->out_channel & inputs[i])) {
289	ch->input = i;
290	ch->in_channel = ch->out_channel;
291	inputs[i] |= ch->out_channel;
292	return;
293	}
294	}
295	}
296
297	static void guess_map_any(AVFilterContext *ctx, ChannelMap *ch,
298	uint64_t *inputs)
299	{
300	int i;
301
302	for (i = 0; i < ctx->nb_inputs; i++) {
303	AVFilterLink *link = ctx->inputs[i];
304
305	if ((inputs[i] & link->channel_layout) != link->channel_layout) {
306	uint64_t unused = link->channel_layout & ~inputs[i];
307
308	ch->input = i;
309	ch->in_channel = av_channel_layout_extract_channel(unused, 0);
310	inputs[i] |= ch->in_channel;
311	return;
312	}
313	}
314	}
315
316	static int join_config_output(AVFilterLink *outlink)
317	{
318	AVFilterContext *ctx = outlink->src;
319	JoinContext *s = ctx->priv;
320	uint64_t *inputs; // nth element tracks which channels are used from nth input
321	int i, ret = 0;
322
323	/* initialize inputs to user-specified mappings */
324	if (!(inputs = av_mallocz_array(ctx->nb_inputs, sizeof(*inputs))))
325	return AVERROR(ENOMEM);
326	for (i = 0; i < s->nb_channels; i++) {
327	ChannelMap *ch = &s->channels[i];
328	AVFilterLink *inlink;
329
330	if (ch->input < 0)
331	continue;
332
333	inlink = ctx->inputs[ch->input];
334
335	if (!ch->in_channel)
336	ch->in_channel = av_channel_layout_extract_channel(inlink->channel_layout,
337	ch->in_channel_idx);
338
339	if (!(ch->in_channel & inlink->channel_layout)) {
340	av_log(ctx, AV_LOG_ERROR, "Requested channel %s is not present in "
341	"input stream #%d.\n", av_get_channel_name(ch->in_channel),
342	ch->input);
343	ret = AVERROR(EINVAL);
344	goto fail;
345	}
346
347	inputs[ch->input] |= ch->in_channel;
348	}
349
350	/* guess channel maps when not explicitly defined */
351	/* first try unused matching channels */
352	for (i = 0; i < s->nb_channels; i++) {
353	ChannelMap *ch = &s->channels[i];
354
355	if (ch->input < 0)
356	guess_map_matching(ctx, ch, inputs);
357	}
358
359	/* if the above failed, try to find _any_ unused input channel */
360	for (i = 0; i < s->nb_channels; i++) {
361	ChannelMap *ch = &s->channels[i];
362
363	if (ch->input < 0)
364	guess_map_any(ctx, ch, inputs);
365
366	if (ch->input < 0) {
367	av_log(ctx, AV_LOG_ERROR, "Could not find input channel for "
368	"output channel '%s'.\n",
369	av_get_channel_name(ch->out_channel));
370	goto fail;
371	}
372
373	ch->in_channel_idx = av_get_channel_layout_channel_index(ctx->inputs[ch->input]->channel_layout,
374	ch->in_channel);
375	}
376
377	/* print mappings */
378	av_log(ctx, AV_LOG_VERBOSE, "mappings: ");
379	for (i = 0; i < s->nb_channels; i++) {
380	ChannelMap *ch = &s->channels[i];
381	av_log(ctx, AV_LOG_VERBOSE, "%d.%s => %s ", ch->input,
382	av_get_channel_name(ch->in_channel),
383	av_get_channel_name(ch->out_channel));
384	}
385	av_log(ctx, AV_LOG_VERBOSE, "\n");
386
387	for (i = 0; i < ctx->nb_inputs; i++) {
388	if (!inputs[i])
389	av_log(ctx, AV_LOG_WARNING, "No channels are used from input "
390	"stream %d.\n", i);
391	}
392
393	fail:
394	av_freep(&inputs);
395	return ret;
396	}
397
398	static int join_request_frame(AVFilterLink *outlink)
399	{
400	AVFilterContext *ctx = outlink->src;
401	JoinContext *s = ctx->priv;
402	int i;
403
404	/* get a frame on each input */
405	for (i = 0; i < ctx->nb_inputs; i++) {
406	AVFilterLink *inlink = ctx->inputs[i];
407	if (!s->input_frames[i])
408	return ff_request_frame(inlink);
409	}
410	return 0;
411	}
412
413	static int try_push_frame(AVFilterContext *ctx)
414	{
415	AVFilterLink *outlink = ctx->outputs[0];
416	JoinContext *s = ctx->priv;
417	AVFrame *frame;
418	int linesize = INT_MAX;
419	int nb_samples = INT_MAX;
420	int nb_buffers = 0;
421	int i, j, ret;
422
423	for (i = 0; i < ctx->nb_inputs; i++) {
424	if (!s->input_frames[i])
425	return 0;
426	nb_samples = FFMIN(nb_samples, s->input_frames[i]->nb_samples);
427	}
428
429	/* setup the output frame */
430	frame = av_frame_alloc();
431	if (!frame)
432	return AVERROR(ENOMEM);
433	if (s->nb_channels > FF_ARRAY_ELEMS(frame->data)) {
434	frame->extended_data = av_mallocz_array(s->nb_channels,
435	sizeof(*frame->extended_data));
436	if (!frame->extended_data) {
437	ret = AVERROR(ENOMEM);
438	goto fail;
439	}
440	}
441
442	/* copy the data pointers */
443	for (i = 0; i < s->nb_channels; i++) {
444	ChannelMap *ch = &s->channels[i];
445	AVFrame *cur = s->input_frames[ch->input];
446	AVBufferRef *buf;
447
448	frame->extended_data[i] = cur->extended_data[ch->in_channel_idx];
449	linesize = FFMIN(linesize, cur->linesize[0]);
450
451	/* add the buffer where this plan is stored to the list if it's
452	* not already there */
453	buf = av_frame_get_plane_buffer(cur, ch->in_channel_idx);
454	if (!buf) {
455	ret = AVERROR(EINVAL);
456	goto fail;
457	}
458	for (j = 0; j < nb_buffers; j++)
459	if (s->buffers[j]->buffer == buf->buffer)
460	break;
461	if (j == i)
462	s->buffers[nb_buffers++] = buf;
463	}
464
465	/* create references to the buffers we copied to output */
466	if (nb_buffers > FF_ARRAY_ELEMS(frame->buf)) {
467	frame->nb_extended_buf = nb_buffers - FF_ARRAY_ELEMS(frame->buf);
468	frame->extended_buf = av_mallocz_array(frame->nb_extended_buf,
469	sizeof(*frame->extended_buf));
470	if (!frame->extended_buf) {
471	frame->nb_extended_buf = 0;
472	ret = AVERROR(ENOMEM);
473	goto fail;
474	}
475	}
476	for (i = 0; i < FFMIN(FF_ARRAY_ELEMS(frame->buf), nb_buffers); i++) {
477	frame->buf[i] = av_buffer_ref(s->buffers[i]);
478	if (!frame->buf[i]) {
479	ret = AVERROR(ENOMEM);
480	goto fail;
481	}
482	}
483	for (i = 0; i < frame->nb_extended_buf; i++) {
484	frame->extended_buf[i] = av_buffer_ref(s->buffers[i +
485	FF_ARRAY_ELEMS(frame->buf)]);
486	if (!frame->extended_buf[i]) {
487	ret = AVERROR(ENOMEM);
488	goto fail;
489	}
490	}
491
492	frame->nb_samples = nb_samples;
493	frame->channel_layout = outlink->channel_layout;
494	av_frame_set_channels(frame, outlink->channels);
495	frame->sample_rate = outlink->sample_rate;
496	frame->format = outlink->format;
497	frame->pts = s->input_frames[0]->pts;
498	frame->linesize[0] = linesize;
499	if (frame->data != frame->extended_data) {
500	memcpy(frame->data, frame->extended_data, sizeof(*frame->data) *
501	FFMIN(FF_ARRAY_ELEMS(frame->data), s->nb_channels));
502	}
503
504	ret = ff_filter_frame(outlink, frame);
505
506	for (i = 0; i < ctx->nb_inputs; i++)
507	av_frame_free(&s->input_frames[i]);
508
509	return ret;
510
511	fail:
512	av_frame_free(&frame);
513	return ret;
514	}
515
516	static const AVFilterPad avfilter_af_join_outputs[] = {
517	{
518	.name = "default",
519	.type = AVMEDIA_TYPE_AUDIO,
520	.config_props = join_config_output,
521	.request_frame = join_request_frame,
522	},
523	{ NULL }
524	};
525
526	AVFilter ff_af_join = {
527	.name = "join",
528	.description = NULL_IF_CONFIG_SMALL("Join multiple audio streams into "
529	"multi-channel output."),
530	.priv_size = sizeof(JoinContext),
531	.priv_class = &join_class,
532	.init = join_init,
533	.uninit = join_uninit,
534	.query_formats = join_query_formats,
535	.inputs = NULL,
536	.outputs = avfilter_af_join_outputs,
537	.flags = AVFILTER_FLAG_DYNAMIC_INPUTS,
538	};
539